Broaching machine



Dec. 8, .1936. M RQMAINE ET AL f I 2,063,756

BROACHINGYMAGHINE Filed March 1, 1953 7 Sheets-Sheet 1 Dec. 8, 1936. M, RQMAINE ET 2,063,756

BROACHING MACHINE Filed March 1, 1933 '7 Sheets-Sheet 2 Dec. s, 1936. M. ROMAINE Fr AL 2,063,756

BROACHING MACHINE Filed March 1, 1955 7 Sheets-Sheet 4 Dec. s, 1936. M, ROMNNE Er AL 2,063,756

BROACHING- MACHINE Filed March 1, 1933 7 Sheets-Sheet 5 1936. M. ROMAINE ET AL 2,063,756

BROACHING MACH INE Filed March 1, 1935 7 Sheets-Sheet 6 Fly-17 I M 275 277 Z Dec. 8, 1936. M. ROMAINE ET AL 2,063,756

' BROACHING MACHINE Filed March 1, 1953 7 Sheets-Sheet '7 Patented Dec. 8,

BROACHING MACHINE Millard Romaine, Cincinnati, and Erwin G.

Boehm, Norwood, Ohio, assignors to The Cincinnati Milling Machine Company, Cincinnati, Ohio, a corporation of Ohio Application March 1, 1933, Serial No. 659,226

8 Claims. (Cl. 90-33) This invention relates to improvements in machine tools and especially to improvements in broaching machines.

An object of the invention is the provision of an improved broach for expeditiously form ing seats or annular recesses on work pieces while the saidwork pieces are being conveyed through the manufacturing line.

Another object of the invention is the provision of a broaching machine adapted to be disposedin a conveyor line in such manner that substantially no interruption in the travel of the work is had as the said work is being manuiactured or processed. 1 r A further object of the invention is the provision of a broach as, above specified which in-.- D

cludes means for receiving the work from the normal conveying system, positioning same with respect to the broach, and-subsequently plac- 2 ing the work in the line for transportation to the next step in'the process of manufacture.

Astill furtherobject of the invention is the provision of improved means associated with the broach for eliminating play and wear between 25 the several parts in all directions.

An additional object of the invention is the provision of a broach for accomplishing the above objects which is substantially automatic in its performance. I

30 It is also an object of the invention to provide a new and improved hydraulic circuit and control means for effecting the operation of the several parts.

Other objects and advantages of the present 0 invention should be readily apparent by reference to the following specification considered in conjunction with the accompanying drawings, forming a part thereof, and it is to be understood that any modifications may be made in the exact structural details there shown and described, within the scope of the appended claims, without departing from or exceeding the spirit of the invention.

In the drawings:

45 Figure 1 is a side elevation of the improved broach illustrated as disposed in the normal conveyor line.

Figure 2 is a top plan view of the machine shown in Figure 1.

50 Figure 3 is 'a fragmentary longitudinal sectional view through the broach supporting table and the mechanism for efiecting the actuation Figure 5 is a fragmentary sectional view taken 'on line 5-5 of Figure 4, illustrating means for disposing of the chips from the broach and forming a detail of the invention.

Figure 6 is a horizontal sectional view taken 5 on line 6-.-'6 of Figure 4 and illustrating the meiins for positioning the table relative to the be Figure '7 is an enlarged fragmentary sectional view taken on line '|--'l of Figure 6. g 10 Figure 8is a fragmentary sectional view taken 7 on line 88 of Figure lillustrating the valve control mechanism for the table.

Figure 9 is a sectional view taken on line 9-0 or Figure 8. 16

Figure 10 is a sectional view taken on line Iii-i0 of Figure 8.

Figure 11 is a sectional view taken on line ll-|i 'of Figure 2 illustrating the distributor and reversing valves for the table.

Figure 12 is a sectional view taken on line |2-|2 of Figure 11.

Figure 13 is a sectional view of the balance valve taken on line i3-l3 of. Figure 1 included in the hydraulic circuit and forming a detail of I the invention.

Figure 14 is a sectional view taken on line "-44 of Figure 13.

Figure 15 is a side elevational view of the work loading and ejecting mechanism, as seen from line l5-I5 on Figure 1.

Figure 16 is a sectional view taken on line I 6- of Figure 15.

Figure 17 is a sectional view taken on line l'|--l1 of Figure 15.

Figure 18 is a horizontal sectional view taken on line I8i8 of Figure 17 and illustrating the work positioning and clamping mechanism.

Figure 19 is a fragmentary sectional view taken on line l9-l9 of Figure 18.

Figure 20 is adiagrammatic view depicting the hydraulic circuit and valve employed for controlling and effecting the movement of the table.

Figure 21 is a diagrammatic view of the hydraulic circuit employed for centralizing, loading and ejecting the work as respects-the machine.

Figure 22 is a sectional'view taken on line 2222 of Figure 6 illustrating the seating of the table cylinder with the bed.

Throughout the several views of the drawings similar reference characters are employed to denote the same or similar parts.

As seen in Figure 1, the machine of this invention comprises an elongated horizontal base or bed 25, the right hand end of which is disposed beneath a conveyor line, indicated generally by the numeral 26. The conveyor line 26 would extend on the right to the machine which operated upon the work prior to the broaching operation, as performed by the machine of this invention. The conveyor 26 comprises, as is 'usual practice, a plurality of rollers 27 or an endless belt or chain for continuously transporting the work. The conveyor 26 terminates adjacent a receiving platform 28 that is carried by the bed 25 of the machine. The platform 28 comprises side members 29 and 39 spaced from one another to receive between them freely rotatable rollers 3| having their ends iournaled in the side members 29. One of said side members, 29 for example, has projecting from it a pair of lugs or ears 32 and 33 respectively lying adjacent bracket members 34 and 35 secured to the side of the bed 25 and extending upwardly therefrom. Pivot pins 36 extend through the lugs 32 and 33 into the brackets 34 and 35. When in operative position, the frame 39 of the carrier rests on additional brackets 31 and' 38 also secured to the bed 25 and extending upwardly therefrom.

From the foregoing it will be noted that the platform'28 may be positioned to expose the parts of the machine lying immediately beneath it and would assume a position shown in phantom lines at v39 in Figure 4. As will later be brought out, the positioning of the platform 23 permits a ready access to the broaches for the inspection or replacement thereof.

From the foregoingit will be noted that the work is shot from the conveyor 26 onto the platform 28 along which it is readily movable due to the freely rotatable rollers 3|. The ma.- chine proper at the left hand terminus of the platform, as seen in Figure 1, is provided with a work receiving and positioning mechanism,- indicated generally by the numeral 49 which includes a base member 4| adapted to be fastened to the bed 25. The base 4| has rotatably journaled thereon a roller 42 which receives the work and transfers same to other rollers associated with a lowering and elevating mechanism associated with the work receiving mechanism 49, as will be later described. The base 4| on the other side of the mechanism 48 has a second roller 43 ,receiving the work from the mechanism 40 after it has been broached and assists in transferring the work to a second' platform 44 which is in all respects identical with the platform 28. The said platform 44 ter-, minates at its other end in a continuation of the conveyor mechanism 26 for conveying the work piece to the next step or next machine in its process of manufacture.

The bed 25 beneath the platforms 28 and 44 and the work loading and ejecting mechanism 49 is provided with-.guideways 45 and 46 on which is mounted 8* table 41 that carries the broaches. In order to eliminate side play and to subsequently take up for wear between the bedways 45 and 46 and the table 41, the following unique novel construction has been provided. 'By reference to Figures 4, 6 and 7, it will be noted that the bed 25 at the inside edges of the guideways 45 and 46 has formed therein grooves 48 and 49 respectively receiving tongues 48 and 5| depending from gibs 52 and 58. The groove 48 is straight or parallel with the direction of extent of the way 45 and is continuous from one end of the way to the other. The groove 49, as seen in Figure 6, is broken up into a plurality of grooves 54, which are parallel to one another, but angular as respects the extent of the way 46. In view of the extreme length of the bed and consequently of the gibs, they are each divided into a plurality of parts having overlapping tongues such as 55 and 56. Each of the gibs 52 is provided with a plurality of holes through which pass screws 5'! for securing same in definite immovable positions. The gibs 53 are each provided with a plurality of counterbored elongated perforations 68 through which pass clamp screws 59.

In order to obtain and maintain proper seat-.

ing of the table 41 on the ways 45 and 46 the table has formed longitudinally thereof flanges 62 and 63. The flanges 62 and 63 are substantially identical in construction and each is provided with a pair of inclined surfaces 64 and 65 extending in opposite directions from a point substantially midway of the length to the outer edges thereof. Mounted on the inclined ways 64 and 65 is a plurality of gibs 66 each having extending therefrom a lip 61 engaging the upper surface of the table flanges 62 and 63. Each of the gibs 66 is provided with a plurality of counterbored elongated perforations 68 through which pass clamp screws 69 for securing the gibs to the ways 64 and 65.

In order, therefore, to secure proper engagement between the table ways 45 and 46 and the bed 25 it is only necessary to loosen the clamp screws 69 and slide the gibs axially relative to the ways 64 and 65, which causes the lips 61 thereof to engage with the flanges 62 and 63, whereupon the said screws are again clamped. From the foregoing it will be noted that the table 41 is properly positioned to eliminate all relative undesirable movement between it and the supporting bed for thereby insuring the movement of the table through a definite unvarying path.

The table 41 has mounted on its upper surface a block 10 to which is secured in this instance a pair of broaches H and I2. It is to be noted, however, that only one, or more than two, broaches may be secured to the block 19, as the nature of the work demands.

The table 41 is actuated relative to the bed by hydraulic means, for which purpose itv has secured to it and depending therefrom a bracket or lug 13 having formed therethrough a perforation through which passes a stud 14. One

end of the stud i4 is threaded to receive a nut .15 for securing the lug 13 between itself and a head I6 formed integral with the stud. On the other side of the head 16, the stud is provided witha threaded tang TI received in a threaded counterbore in one end of a hollow piston rod 18. The other end of the rod 18 is also provided with a threaded counterbore receiving a threaded tang on one end of a stud 19, which is similar in all respects to the stud 14. The stud I9, however, is secured in a suitable piston 80 adapted to be reciprocated through a cylinder 8| which is mounted securely to the bed 25.

. The cylinder 8I has secured to its outer end a head 82 through which are formed ports 83 and 84 for connecting a hydraulic medium with the interior of the cylinder. For this purpose the port 83.receives one terminus of a conduit or pipe 85 of a hydraulic actuating and control system which will be later described in detail. The cylinder. 8| extends through a cradle or support 88 that is secured to and extends upwardly from the bed 25 and supports the cylinder intermediate its ends. The other or inner end of the cylinder 8| is closed by a combined cylinder head and stufllng box 81 in which are formed ports 88 and 89 for connecting the hydraulic system with this end of the cylinder. For this reason the port 88 also receives the terminus of a hydraulic conduit or pipe 90 of the hydraulic system above referred to. The cylinder head and stufllng box 81 is formed on opposite sides with a relieved or cut away portion to form seats III and 92 received on similar seats 93 and 94 provided by the bed 25. In addition, the head 81 has flaring from it and above the seats 9| and 92, ears or lugs 95 and 98 having formed therethrough a plurality of bores through which clamp screws 91 pass for securing the cylinder immovably to the bed 25. In order to position the cylinder with respect to the bed and to avoid the thrust of the hydraulic pressure being directed on the clamp screws 91, the cylinder head seats against a circular flange 98 formed integral with the bed 25. The head 81 on its other end has a plurality of axially adiustable abutments 99adapted to engage with lugs or ears I00 extending from the bed 25. In other words, the cylinder is. axially positioned and clamped to the bed between the flange 98 and the lugs I00 prior to the fastening thereof by the clamp screws 91. By this construction the end thrust on the cylinder is taken by integral parts of the bed itself and thereby ,relieves the strain on the clamping and holding mechanism.

The hydraulic system for effecting and controlling the movement of the piston and consequently of the table connected thereto, is diagrammatically illustrated in Figure 20 and as there shown comprises a sump or tank IIII for containing the fluid, preferably oil, utilized in the system. In view of the large quantities of oil necessary to effect the operation of the parts, there is shown a pair of pumps I02 and I03 respectively having a suction line I04 and I05 for drawing the fluid from the tank and discharging said fluid under pressure into conduits or lines I08 connectedwith each pump. A pressure control or relief valve I01 is provided for determining the pressure in the line I08 with which line is also connected a suitable gauge I08. The line I08 has a branch line I09 and they terminate in a valve, indicated generally by the numeral H0 and constituting a directional control or reversing valve. The valve III) connects the line I08 or its branch line I09 with either three conduits III, H2 and H3, the latter extending directly to the tank of sump IOI for short circuiting the system and the other two terminating respectively at the right and left hand ends of the cylinder8l. The line II I shown diagrammatically in, Figure 20 is the same as the pipe or conduit shown struc turally in Figure 3, while the line II2 diagrammatically shown in Figure 20 is structurally shown as pipe or conduit in Figure 3. The valve I I0 is shown in Figure 20 as in position to short circuit the system and return thefluid in the lines I08 and I09 to the sump or tank IOI. As also shown in this figure, between the reversing valve I I0 and the piston and cylinder there is provided a second valve for permitting, when in the proper position, the rapid escape of the fluid from one side of the piston and indicated generally by the numeral II4.' This valve H4 is connected by a line or conduit II5 with the line or conduit H2 extending from the left hand end of the table cylinder. The other side of the valve II4 is connected by the line or conduit II8 with the conduit sump or tank "II.

The valves I I0 and H4 are shown structurally in Figure 11 as enclosed within a single casing II1 having a pair of bores formed therein and disposed one above the other. Within the longer bore is the reversing valve which comprises a valve bushing II8 having formed therethrough sets of radial ports H9, I28,. MI, I22,

H8 terminating in the I23, I24, I25 and I28, each set being connected by a circumferential groove I21 formed on the exterior of the bushing. Extending through the bushing bore is a spool type valve I28 having cannelures I29, I30 and I3I for connecting certain of the sets of radial ports in different combinations. The chamber containing the bushing H8 is closed at opposite ends by heads I32 and I33 which are substantially identical in construction and in each of which is mounted a guide I34 for a headed sleeve I35 and a piston plunger I38. The guides I32 and I33 are further provided with chambered plugs I31 through which the head of the sleeve I35 shifts and connected with the outer end of the, plugs I31 is one end of a conduit I38 of a control hydraulic system to be later described and which effects the shifting of vthe valve I28.

The rapid traverse control valve H4 is mounted in the shorter of the bores in the casing H1 and comprises a bushing I39 similar to the bushing II8 which has formed therethrough sets of radial ports I40, I, I42, and I43. In the bore through the bushing I39 is a spool type valve I44 having a cannelure I45 adapted in one position to connect the sets of ports I and I42 and in the other position to interrupt the connection thereof. The ends of the chamber containing the bushing I39 are closed in the same manner as the'ends of the chamber containing the bushing H8 and the said closures each have mounted therein a piston plunger I48 and I41 of different areas, whereby with equal pressures on the ends thereof, the valve will be shifted by the larger piston plunger I41 for a purpose that will be later made clear. The said chamber closures also each include a plug I48 and I49 with which is respectively connected one terminus ,of conduits I50 and I5I which are a "part of the control hydraulic circuit above referred to.

The hydraulic control circuit above referred to comprises a. pump I52 having a suction line I53 for drawing the hydraulic fluid or medium from the tank WI and discharging same into the line or conduit I54. The line I54 trminates at a. pilot valve indicated in its entirety in Figure 20 by the numeral I55. The valve I55 is adapted in one position to connect the hydraulic medium with a pair of lines or conduits I58 and I51 which respectively terminate in lines or conduits I58 and I59. The conduit I58 in turn connects i the right hand ends of said valves. The valve the is also adapted in different positions thereof, to connect the line ib l independently with either line tilt or it? and to connect the other with branch conduits or lines Hill and let which terminate in lo 'a common discharge line 52 that has its terminus in the sump or tank mi whereby the reversing or directional control valve and the rapid traverse valves are shifted to difierent operative positions.

The pilot valve 855 and mechanism for controlling and operating it is shown structurally in Figures 8, 9 and 10, particularly in Figure 9.. As there shown, the valve comprises a casing flit mounted within a recess ltd formed in a bracket i 9135 bolted to the face of the bed 251. The bracket M55 is secured to the forward face of the bed 25 and a corresponding bracket is secured to the rear face thereof, which brackets support the base M of the loading and ejecting mechanism and constitute a bridge on which the work finally comes to rest while being operated upon. The valve casing use has formed therein a bore in which is pressed the valve bushing its. having formed therethrough a plurality of sets of radial ports Hell, [16%, its, lit and iii with which theends of conduits 9655i, 1157?, 95d, b and let respectively connect. Extending through the bushing ltd is a spool type valve. i'it having formed thereon cannelures ills. lid and H5 i which in the several positions or the valve connect the conduits or complete the different circuits above enumerated. The valve H2 formed integral therewith a stem in which is formed a notch ilii receiving the ball end ill i-oi a load and fire dog lit. The dog lift is l rovided with two shallow notches lit and ltd intermediate which is ,a notch Hill. The several notches are connected by contoured or cam shaped walls which co-operate with the nose 882 I of a latch i853 pivoted at ltd within the recess H56 01 the bracket let. A spring ltd has its one end anchored to the bracket 9% and its other end connected with the latch H63 for yieldingly urging the latch about its pivot to cause engagement between the nose i132 thereof and the load and fire dog M78.

The operation of the load and fire dog is such that with the valve in the position as shown in Figure ,9, the latch its engages the shallow notch 5 lift) for holding the valve in its extreme left hand -position and a slight movement or the valve to the right will disengage the notch W9 and latch, causing said latch to ride over the peak or apex of the joined walls of the notches are and let whereupon the valve will be actuated to its neutral position until the latch is in the deep notch idi thereof. When the valve is in its extreme right hand position, the latch is engaged with the shallow notch lull whereupon a slight movement of the dog or valve in the opposite direction results in the reverse movement of the parts until the latch again comes to rest in the large 7 or deep notch iiii. I

The dog He is secured to a shaft its which 7 spans the recess toil and projects beyond the limits ,of the bracket ltd and is iournaled at one end in said bracket and on the other end in a plate It?! secured to the face of the bracket I65. To the rear end of the shaft its, which extends .beyond the Journal thereof in bracket- I855,

has

aooavec is secured an elongated arm I88 having journaled in each end thereof a roller I89 and I90. The rollers E89 and itil are adapted to be respectively engaged by cam faces I M and I92 formed on reversing dogs 893 and I94 adjustable through slots H95 and H96 formed in or secured to the side of the table 6?.

The operation of these parts is as follows: With the dog lit in the position shown in Figure 9 and the arm wt in the position shown in Figure 10, the table ti is moving to the right, as seen in these figures. The table carries with it the dog tilt the cam face Hit of which will eventually engage the roller W9 and tend to depress same thereby oscillating the arm E83, shaft I86 and dog lit in a counterclockwise direction, un-

seating the latch let from the shallow notch H9 whereupon the camming action or the firing of the latch H83 and dog M8 by' the spring 585 is had, as above described for returning the pilot valve to its normal or neutral position. The dog itii and consequently the valve H2 are initially shifted by manual means, for which purpose the shaft i535 journaled in the plate i8? projects beyond the said plate to receive a manually operable lever iii'i. The lever in addition to initially setting the valve and initially setting the load and fire mechanism also acts as a directional. indication lever so that the table will move in the direction in which the lever is shifted.

In the operation of the control circuit or mechanism, the lever it? has three positions, indicated in Figure 20 as rapid return", stop and feed. The parts are shown with the lever i9? in its neutral or stop position at which time. as above described, the pressure from the pump H52 through the line th t is connected by the cannelure Hi l of the pilot valve H2 with the conduits or lines H56 and it'll. The same pressure will therefore be in the lines H8 and I59 and consequently in the conduits I59, itii, I382, and ltd. These conduits direct the pressure against piston plungers Ml, i 36, Hits, and I36. Since the piston plungers 03% and IBM are of the same cross section it will result in the centralization of the reversing valve H28, as shown in Figure 20, while since the piston plunger Mi is of a greater cross section than the piston Mt, it will result in the valve itii being shifted to its extreme right hand position. At this time then the pressure in line [1% from the pumps in and. tilt will be short circuited through the branch line we, cannelure I135 of the valve its with the return conduit @{WhiOh terminates in the sump or tank lei, resulting therefore in no movement of the table. At the time of shifting of the piston plungers 936, Elite, and t ll the exhaust medium ahead of these plungers was respectively exhausted through ports its, I26 and its which respectively connect with branch exhaust lines 1198, liisand 2W each of which is connected with a conduit or port 260 and in turn emptying into a conduit or port 202 connected with a conduit 2% terminating in the sump or tank Nil. 1

If the lever i9! is now shifted to the right or to the feed position, as shown in Figure 20, the pilot valve would be shifted to the left and thereby connect through the cannelure I14 the lines I54 and B56 and would connect through the cannelure H3 the lines I51 and I60. At this time the conduit I58 and conduits I38a and I 5| would be under pressure while the conduit I59 and conduits I38: and I50 would be connected to the exhaust. Since the rapid traverse valve Mt would already be to its right hand limit of movement no further movement would be imparted thereto, but by relieving the pressure on the piston plunger I36 the reversing valve I28 would be shifted to its extreme right hand position. This then would uncover the port I23 and cover the port I25 so that the pressure in the line I06 would be coupled or connected through the cannelure I30 with the conduit H2 and act on the left hand face of the piston, thereby moving the table to the right. At this time the exhaust ahead of the piston would be connected through the conduit III to the port I22 and through the cannelure I29 with the port I20 and a conduit 204 connected therewith. The conduit 204 passes through a back pressure balancing valve indicated in its entirety by the numeral 205, which will be explained in detail later. The table will continue to move in a direction toward the right at a feeding rate of speed until one of the table dogs H2 or I93 engages with its roller on the arm I88 and thereby shifts the valve to its neutral .or stop position, whereupon the table will be brought to a standstill.

The lever I91 is now shifted to the left or to the rapid traverse position for thereby connecting the control pressure line I54 with the line I51 and connecting the line IBI with the line I56. This then reverses the pressures in conduits I58 and I59 and consequently in the control conduitsto the piston plungers. In other words piston plungers I46 and I36 are'now under pressure for shifting the rapid traverse valve I44 to its left hand position and shifting the reversing valve I28 to its left hand position. At this time the full capacity of the pumps I02 and I03 is being discharged into the small end of the cylinder, that is, the end through which the large piston rod is disposed. Since the capacity on both sides of the piston is thereby greatly changed, the piston and parts carried thereby will tend to move at a rapid rate. And to insure that the oil or other hydraulic medium can escape fast enough from the large end of the cylinder, use is made not only of the conduit II2 through the conduit II3, but also through the branch conduit II5 which is at this time connected with the conduit H6 and conduit II3. From this it will be seen that the piston and parts operated thereby are travelling at a. rapid rate toward their initial position. This movement continues until the other dog I93 or I94 on the table engages the other of the rollers on the arm I88 and again returns the valve to its neutral or stop position.

The back pressure valve 205 is employed for insuring a continuous even movement of the table and consequently the cutters and to eliminate any possible surging or running ahead thereof. This valve is shown structurally in Figures 13 and 14 and comprises a casing 206 secured to the bed 25 and having formed therein a chamber containing the valve bushing 201 through which sets of radial ports 208, 209, 2I0, 2N, 2I2 and 2I3 are formed. Extending through the bore in the bushing 201 is a spool type valve 2I4 having a cannelure 2I 5 for controlling the connection of ,ports 2I0 and 2I I. Also mounted in the bore in the bushing 201 is a sleeve 2I6 in which is disposed for movement relative thereto a piston plunger 2I1 adapted to abut one end of the piston valve 2I4. Closing this end of the bushing bore is a plug 2 I8 having threaded therein the screw 2I9 forming .one abutment for a spring 220 that abuts on its other end with the piston plunger 2I1. Mounted in the bore of the bushing 201 on the other side of the valve 2I4 is a shiftable abutment 22I contacted on one side by a spring 222, whose characteristic and effective length may be varied by means of a screw 223 with the threads of which the spring 222 meshes. The screw 223 is threaded through a plug which closes this end of the bushing bore.

Referring now to the diagrammatic illustration in Figure 20, it will benoted that the normal discharge line from the reversing valve IIO has extending from it three conduits 225, 226 and 221. Conduit 225 is connected with the bushing port 2-I3 and therefore places the pressure on the outer end of the piston plunger 2I1 equal to the pressure in the line 204. The conduit 22B connects with the port 2 and has a resistance therein which is relatively low and consists of a coil or pipe 228 having a comparatively small bore therethrough. The conduit 221 connects with the port 209 and also has a hydraulic resistance therein which is comparatively high as respects the hydraulic resistance 228 and also comprises a coil 229 having a bore therein smaller than that in the coil 228. The-port 2I0 is connected by a discharge pipe 230 with the sump or tank IOI. The ports 208 and 2I2 are connected by branch conduits 23I and 232 with the discharge conduit 203 and constitute drains for draining the hydraulic medium that may leak past the piston plunger 2I1 and spring abutment 222.

The operation of this valve is as follows: When the table is moving in a feeding direction the discharge fluid from the piston and cylinder is, as above described, into the conduit 204 from which it passes through conduits 225, 226 and 221. The pressures therefore in the chamber ahead of the piston plunger 2I1 and in the chamber ahead of the spring abutment 222 will be equal for thereby centralizing the valve 2I4 and connecting the ports 2 and 2I0 to permit a continuous flow of fluid through the conduit 226, hydraulic resistance 228 and conduit 230.

into the sump or tank IN. This will continue so long as the tool is feeding at a uniform rate, but should the tool attempt to coast ahead a greater amount of fluid would then be discharged into the conduit 204 which would immediately build up the pressure ahead of the piston plunger 2I1 causing same to advance and thereby closing down on the discharge through the port 2 and immediately slowing up the movement of the tool. The pressure, however, will then be forced through the resistance 229 into the chamber ahead of the spring abutment 222 and thereby again balance the pressures and force the piston back to its normal position,

' allowing the tool to advance at its normal desired rate. This shuttling back and forth of the valve 2I4 would continue until the tool again settled to a constant uniform feeding rate.

The mechanism for lowering the work into position for operation thereon and subsequently ejecting same and for centralizing and clamping it, is illustrated in Figures 15 to 19, inclusive, and Figure 21. This mechanism comprises the base plate 4| above referred to, to which is secured a pair of frames 233 and 234 which are connected to one another. Disposed within this frame is an elevating and lowering mechanism comprising a pair of bars 235 and 236 each being provided with a plurality of rollers 231 which when in an elevated position are in the same plane as theconveyor rolls 21 and 3I and receive the work from the said rolls ti. Extending upwardly from each of the bars 235 and 236 is a pair of arms 236 and 239 which have their upper ends pivoted respectively at 2st and 2M to gears 2 32 and 2%. The gears 262 are keyed or otherwise secured to a shaft 2% which is iournaled in the frame 2% while the gears 2 353 are likewise keyed or otherwise secured to a shaft 2% journaled in the frame 238. Above one set of gears 262 and 2&3 the frames 233 and 23 3 are provided with an aperture 2% in which is disposed for axial movement relative thereto a rack bar Ml meshing with the gears 262 and 263. One end of the rack bar itll is connected as at 248 with a piston rod 2% extending from a piston 250. The piston t lt is in turn enclosed within a cylinder 25$ secured in any desirable manner to one of the frames, 2% for example.

The piston 2% is adapted to be operated by a hydraulic fluid, such as air for example, as shown in Figure 21. As there shown, an air pressure line 252 is provided from which the conduit 253 extends and terminates in a three way valve As illustrated in Figure 21, the valve member 255 is positioned to connect the conduit 25% with the conduit 2% terminating at one end of the cylinder 25K] and thereby shifting the piston to the left. The other end of the cylinder 25H is opened to the atmosphere through the conduit Ztll which terminates in the valve 255.

From the foregoing and due to the eccentric mounting of the arms 288 and 239 on the ears 262 and 2%, it will be noted that as the said gears are rotated in a given direction the arms will be raised and consequently the bars 235 and 23s, while a reverse rotation thereof will cause the said arms and bars to be lowered. The parts are so arranged that the rollers 23?! disappear into recess 25s below the upper surface of the base il, leaving the work to be operated upon resting on said base.

The work in actual practice is actuated toward the right, as seen in Figure 17, and is moved onto the rollers 237 until it is arrested by the abutment 259, here shown as a screw. This screw passes through the end of a lever 2st illustrated as large flanges 2% and 2% projecting inwardly from the frames and between which the work is actuated on to the lowering and elevating rollers 23?.

The work after being positioned on the base til is then finely adjusted and positioned, for which purpose, the following mechanism is provided. A master or final abutment 265 is provided being carried by the base ti and against which one edge of the work is forced. The other end of the work is adapted to be engaged by spring loaded pusher pins 266 and 26? slidably mounted in a block 288 projecting upwardly from the base 49. Contacting with the free ends of the pusher pins 266 and 267 is a wedge member 269 having a dove-tailed connection at 218 with a slide 216 carried by the base plate H. The wedge 269 is secured to the free end of a piston aooavce rod 272 which carries at its other end a piston 218 within the cylinder 2143.

The particular work piece here illustrated has a plurality of ribs or portions intermediate its ends which are adapted to be individually and 5 successively engaged by the broaches during the operation thereon. It has been found desirable to back 'up these portions of the work and for this reason a plurality of backing up members have been provided which are of the same con- 10 struction and it is, therefore, deemed suflicient if but one of them be described in detail. This comprises a fixed slide member 215 having a dove-tailed connection 275 with a movable wedge 21?. The formation of the wedge is such that v 15 the faces of the dove-tailed connection are at? an angle to one another whereby the outer operative face of the sliding wedge block 211! is always parallel with the portion of the work with which it is engaged. The wedge block 2" has pivotally connected to it at tilt one end of a lever 219 which is intermediately pivoted at 210 to a fixed part of the mechanism. The other end of the lever 219 has a pin and slot connection at 288 with a piston rod 282 slidable through suitable guide provided in the base it. The piston rod 282 is connected to a piston 283 within the cylinder 2% and carried by the base plate 38. As was above noted, there is a plurality of these backing up mechanisms provided, in fact, one for each portion of the work to be broached In practice it is desired that the work be first positioned by engaging the fixed abutment block whereupon the backing up members are operated and the pressure on each of them equalized. To accomplish this, hydraulic means, preferably compressed ain'has been provided for operating the parts and, as seen in Figure 21, comprises a conduit 285 extending from the pressure conduit 252 and terminating in three way valve 286. The valve member 2M of this valve is so positioned as to connect the conduit 2% with conduit 288 which terminates in the control valve 289. The 7 control valve 289 is adapted to insure the operation of the work clamping mechanism prior to the operation of the backing up members and therefore comprises a casing 29E through which a pair of ports 2M and 292 are provided. Within the casing 29G) is a piston 293 normally held to the left by spring 29 5 for closing ofi communication through the port 292. Therefore, when the valve member 287! is actuated, the pressure passes through the conduit 286 into the conduit 2% to the cylinder 236 for first actuating the piston 2W3 therein. As soon as this piston has reached the limit of its movement, the pressure builds up in the casing 2st) and actuates the piston 293 therein against the resistance of the spring 2% thereby uncovering the port 292 and establishing a connection or communication between the conduit 288 and conduit 296 extending from the port 292. The conduit 298 is connected by branch conduits with each of the equalizing cyl- .has mounted on its upper surface a cylinder 298 containing apiston 299 from which extends a piston rod 300. The piston rods "0 are each provided with a clamping shoe Ill adapted to normally prevents the flow of compressed air engage the upper surface of the work. These cylinders are also connected by a conduit 302 through a three way valve 303 and conduit 304 with the compressed air line 252. In view of the fact that they are connected with the same line, equal pressures will therefore be had on each of the clamping shoes. The exhaust ahead of said pistons is connected with branch conduits to the conduit 305 that terminates at the valve From the foregoing description it will be noted that there has been provided a broaching machine adapted to be inserted within the normal manufacturing line which comprises a continuous conveyor for transporting work pieces to successive machines for successive operations thereon. It will be noted that the work is readily positioned and operated upon, whereupon it is immediately started on its journey to. the next machine in the line. It is believed that the novelty and advantages of the broach here described will be readily understood.

In order to dispose of the chips carried along by the broach, there is provided a novel mechanism therefor. This consists of a chip receiving chute 306 mounted on the bed beneath the platform 28 and which has a plurality of mouths 301 into which the chips are blown for delivery to suitable receptacles placed at the end of the trough. The chips are blown from the cutters and table by compressed air passing through nozzles 308 and 309 each connected with'a pipe 3l0 that terminates ata valve 3| l. The valve 3| I from the pipe 3|2 into the pipe 3l0. This is done by valve member 3|! spring loaded as'by a spring 3 which has contacting with its free end the nose 3| 5 of a dog 3 pivoted at 3" to the end of the valve housing 3| I. As the table 41 moves along, it' carries with it a dog 3|8 adapted to engage the latch 3|0 for opening the valve 313 and thereby blowing the chips, as above described. This valve is shown structurally in Figure 5 and-diagrammatically in Figure -21 and is connected in with the normal compressed air line 252.

What is claimed is:

1. A work receiving and positioning mechanism for use with broaching machines disposed in the normal processing line which includes a convey0r the combination of a work support, a frame associated with the work support receiving the work from the conveyor, means carried by the frame for positioning the work with respect to the work support, hydraulically actuated means for lowering the work onto the support,

hydraulically actuated means for positioning the work on the support, and hydraulically actuated v means for clamping the work on the support after it has been positioned, said work having a plurality of rib-like portions each of which is adapted to be machined, and hydraulically actuated means for backing up said rib-like portions of the work.

2. A conveyor line broach of the nature disclosed including a fixed bed member having a work receiving seat, a conveyor section overlying said seat in position to receive a work piece from the conveyor line, means for depress,- ing the conveyor section to deposit the work piece on the bed, means for clamping the deposited work piece on the work receiving face of the bed, broaching means contained within the operation on a heavy work piece, such as an automobile engine block, comprising a rigid, hollow bed member having a longitudinal slot in the upper face thereof, a broach supporting table translatably mounted within the bed, broaching means carried by the table and projecting through the slot in the bed, the bed having a work receiving face formed thereon adjacent the slot, means for securing a work piece in position on said face of the bed with a portion overlying the slot for engagement by the broach on the broaching table, and hydraulic means for effecting a translation of the table and supported broach with respect to the work for performance of the broaching operation thereon.

4. A production line broaching machine of the character described including a bed having work receiving seats and a broach longitudinally reciprocable with respect to said seats, supports rising from the bed adjacent the seats, a work supporting mechanism carried by the supports and including depressible members proiectable into a plane below the seats, whereby a work piece positioned thereon will be lowered into engagement with the seats, means for effecting a lowering of said mechanism, a work positioning abutment carried by the bed adjacent the seats in position for engagement with a lowered work piece, means for eflecting a lateral shifting of a work piece when on the seats to clamp the same against the abutment and additional means for clamping the work piece against the seats to maintain the same in position against the thrust of the broach.

5. A mechanism for effecting the broaching of heavy articles, such as automobile cylinder blocks, includingspaced roller conveyor members, a bed unitsub-tending said conveyor members and having an upper work receivingsur face, asectional work'conveyor mechanism carried by the bed in alignment with the other conveyor sections for reception of a work piece therefrom, means for effecting a movement of said mechanism in the direction of the bed to position a supported work piece on the work receiving portion of the bed, means for clamping a positioned work piece with its lower face in engagement with the seating portion of the bed, broaching means reciprocably mounted on the .flanges of the bed for supporting work on its progress to and beyond the machine, a depressible and elevatable conveyor section supported by the bed adjacent said work supporting flanges, means'for effecting a depression of said section to place a supported work piece on the bed flanges, means for securing the work piece in position .on said flanges, hydraulic means for efiecting a controlled feeding traverse of the broach with respect to the work while in clamped 75 position on the flanges and for effecting a rapid traverse retraction of the broach when the movable conveyor section is in elevated position, supporting the work out of the path thereof.

7. A broach for the purpose described including a hollow bed, of ways contained within the bed, a table member slideably mounted upon the ways, means for hydraulically efiecting' a. ieedingmovement of the table in one direction and a rapid traverse movement thereof in the opposite direction, a surface broach member rigidly mounted upon the table and movable therewith for performance ota breaching operation, spaced worl; supporting portions rising from the bed and extending in overlying relation with the table, the spacing of said members providing a slot through which the broach on the table projects, and means for securing a work piece to the bed in spanning relation to said slot whereby traverse of the broach will cause the same to operate on the intermediate portion of the work piece which spans said slot.

8. A broach for the purpose described includaoearse ing'a hollow bed, of ways contained within the bed, a table member slideably mounted upon the ways, means for hydraulically effecting a feeding movement of the table in one direction and a rapid traverse movement thereof in the opposite direction, a surface broach member rigidly mounted upon the table and movable therewith for performance of a broaching operation, spaced work supporting portions rising from the bed and extending in overlying relation with the table, the spacing of said members providing a slot through which the broach on the table projects, means for securing a work piece to the bed in spanning relation to said slot whereby traverse of the broach will cause the same to operate on the intermediate portion of the work piece which spans said slot, and pressure responsive means carried by the bed and efiective during feeding movement to dampen surging of the table and its supported broaching tool with respect to the bed.

MILLARD ROMAINE. ERWIN G. ROEHII. 

